Itbs with plenum or without

[Fernflex]

Hi,

What are the Pro's and Con's about using a plenum like most of the M engines or just using the itbs open?

[UserError]

The main benefit of using a plenum is that it enables you to use a filter more easily, or use forced induction. If it's properly engineered, you won't sacrifice much if any horsepower, and don't have to use those silly looking socks over the intake trumpets.

[Justin B]

A plenum will not only give you a cooler intake charge (rather than inhaling engine bay heated air) but IF it is properly sized, it can boost performance by working with the intake charge reverberations caused by the valves opening and closing. As for cons, well, theyre stupid expensive, and as far as I know, there aren't any specifically for an m20. Got math and fiberglass skills?